Power semiconductor device such as power diodes or power transistors are capable of blocking high voltages of several 10V, several 100V or even several kilovolts (kV). A high blocking voltage is associated with high electric fields in a semiconductor body in which active regions of the semiconductor device are integrated. Especially surfaces of the semiconductor body where high electric fields occur in a blocking state are very sensitive and require a suitable treatment in order to prevent degradation effects that may result in a reduction of the voltage blocking capability. Such treatment usually includes the formation of a passivation layer on the surface. A suitable conventional passivation layer material is, e.g., a semiconductor oxide, such as silicon dioxide SiO2.
There is a need to provide a semiconductor device with a mechanically and chemically very robust passivation layer.